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71.
Mahapure SA Ambekar JD Nikam LK Marimuthu R Kulkarni MV Kale BB 《Journal of nanoscience and nanotechnology》2011,11(8):6959-6962
Hydrogen is a future fuel and hence production of cheap hydrogen is an important area of research. Recently, the photocatalysts were used to generate hydrogen from water and hydrogen sulfide splitting under solar light. Hence, we designed Zinc Indium Vanadate, a novel visible light active photocatalyst and used for the generation of hydrogen by using solar light. We have demonstrated the synthesis of ZnIn2V2O9 (ZIV) catalyst by sonochemical route using NH4VO3, In (NO3)3 and Zn(CH3COO)2 as a precursors and PVP as a capping agent. The obtained product was further characterized by XRD, UV-DRS and FESEM. The XRD pattern reveals the existence of monoclinic crystal structure and broader peaks indicating the nanocrystalline nature of the material. The particle size was observed in the range of 50-70 nm. The optical study showed the absorption edge cut off at 520 nm with estimated band gap about 2.3 eV. Considering the band gap in visible range, ZnIn2V2O9 was used as a photocatalyst for photodecomposition of H2S under visible light irradiation to produce hydrogen. We observed excellent photocatalytic activity for the hydrogen generation by using this photocatalyst. 相似文献
72.
Maityt D Pradhan P Chandrasekharan P Kale SN Shuter B Bahadur D Feng SS Xue JM Ding J 《Journal of nanoscience and nanotechnology》2011,11(3):2730-2734
In this paper, we report single step synthesis of hydrophilic superparamagnetic magnetite nanoparticles by thermolysis of Fe(acac)3 and their characterization of the properties relevant to biomedical applications like hyperthermia and magnetic resonance imaging (MRI). Size and morphology of the particles were determined by Transmission electron microscopy (TEM) while phase purity and structure of the particles were identified by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). Magnetic properties were evaluated using vibrating sample magnetometer (VSM) and superconducting quantum interference device (SQUID) measurements. The as prepared nanoparticles were found to be superparamagnetic with the blocking temperature of 136 K and were easily suspendable in water. Cytotoxicity studies on human cervical (SiHa), mouse melanoma (B16F10) and mouse primary fibroblast cells demonstrated that up to a dose of 0.1 mg/ml, the magnetite nanoparticles were nontoxic to the cells. To evaluate the feasibility of their uses in hyperthermia and MRI applications, specific absorption rate (SAR) and spin-spin relaxation time (T2) were measured respectively. SAR has been calculated to be above 80 Watt/g for samples with the iron concentration of 5-20 mg/ml at 10 kA/m AC magnetic field and 425 kHz frequency. r2 relaxivity value was measured as 358.4 mM(-1)S(-1) which is almost double as compared to that of the Resovist, a commercially available MRI contrast agent. Thus the as-prepared magnetite nanoparticles may be used for hyperthermia and MRI applications due to their promising SAR and r2 values. 相似文献
73.
Chemical looping reforming (CLR) is a new technology for syngas generation. The theoretical process design aspects of syngas generation using CLR of isooctane (gasoline) are studied in this paper to assess its ability for fuel processor development for solid oxide fuel cells. The fuel processor operating conditions for maximum syngas generation at thermoneutral conditions are determined in this study using nickel oxide as oxygen carrier for different inputs of oxygen carrier within the temperature range of 600–1,000 °C at 1 bar pressure. The thermoneutral temperatures for the dual reactor fuel processor were calculated using the hot product gas stream and exothermic CLR process enthalpy to completely balance the endothermic process requirements. The thermoneutral point of 879.5 °C (NiO input of 7 moles) delivered maximum syngas (13.92 moles) using lowest amount of air (26.13 moles) in the process was found to be the most suitable thermoneutral temperature for the fuel processor operation. The novel fuel processor design can also be used for other fuels and oxygen carriers. 相似文献
74.
SiO2 thin films are in high demand for wide range of applications including microelectronics, optoelectronics, solar energy conversion, photocatalysis, and self-cleaning coatings. The performance of thin film is strongly influenced by surface properties like surface roughness, thickness, morphology, wetting behavior, and thermal stability. In these applications, the SiO2 sols were prepared using tetraethylorthosilicate as a source of SiO2 and deposited on 100?×?40?×?2?mm3 glass slide using dip-coating method for 2?min and calcined at 250?°C for 30?min. The SiO2 thin films were obtained using DTAB, SDS, and Tween 20 (Tw 20) surfactants with the thickness of 36.92, 47.15, and 52.39?nm, respectively. Surface morphology was studied with AFM and surface roughness was depicted with 0.9528, 3.6534, and 0.9294?nm. Contact angle measurements have been performed with goniometer to evaluate the wetting behavior of the film. The contact angle of 58.01°, 48.40°, and 37.88° was observed with SDS, DTAB, and Tw 20 film, respectively. The SiO2 thin films with SDS showed more surface roughness and water repelling ability when compared to DTAB and least with Tw 20. 相似文献
75.
Paresh H. Salame Om Prakash A. R. Kulkarni 《Journal of the American Ceramic Society》2013,96(7):2184-2189
The pristine layered cuprate Pr2CuO4 samples of >95% density were fabricated as thin disks. The samples, analyzed by X‐ray diffraction and Scanning electron microscopy, showed clean T′‐type phase with Rietveld refined lattice parameters a = b = 3.95805(±5) Å and c = 12.2262(±5) Å. The measured dielectric properties of the Pr2CuO4 ceramics, in the temperature range ?100°C–150°C and frequencies (ν) 0.1 Hz–1 MHz, showed extremely high εr′ > 104 (above ?30°C), and dissipation (tan δ = εr′′/εr′) between 0.1 and 5 (for 500 Hz ≤ ν ≤ 1 MHz, and ?100 ≤ T ≤ 150°C). The ac conductivity of Pr2CuO4 ceramics ranged between 10?6 and 10?3 Scm?1 for the measured frequencies and temperatures, and showed frequency‐dependent double power law behavior akin to a modified Jonscher's power law. 相似文献
76.
In this paper, we depart from the literature on electricity consumption–real GDP in that for the first time we examine the reaction of real GDP to shocks in electricity consumption. To achieve this goal, we use the structural vector autoregressive (SVAR) model and examine the impact of electricity consumption shocks on real GDP for the G7 countries. We find that except for the USA, electricity consumption has a statistically significant positive impact on real GDP over short horizons. This finding implies that except for the USA, electricity conservation policies will hurt real GDP in the G7 countries. 相似文献
77.
Mg–Ni multilayers and Ni-rich Mg thin films were deposited by electron gun and pulsed laser deposition, respectively. Samples were submitted to thermal treatment in deuterium or hydrogen atmosphere at 423 K and 105 Pa pressure to promote the metal to hydride phase transition.The H chemical bonding in the multilayer samples, after annealing in H2 atmosphere, was examined by Fourier transform infrared spectroscopy: the obtained spectra suggest that the samples with the Mg:Ni=2:1 atomic ratio contain the Mg2NiH4 phase while the samples with lower Ni concentration contain both the MgH2 and the Mg2NiH4 phases.The effect of the Ni additive on the stability of the deuteride phase was studied by thermal desorption spectroscopy (TDS). The TDS spectra of the single-phase Mg2NiD4 samples show a TDS peak at 400 K. The TDS spectra of the two-phase samples show both the D2 desorption peak at 400 K and a second peak at higher temperature that we attributed to the dissociation of the MgD2 phase. The high-temperature peak shifts to lower temperatures by increasing the Ni content.It is suggested that in the two-phase samples, the lattice volumes having the Mg2Ni structure resulting from the dissociation of the Mg2NiD4 phase reduce the thermodynamic stability of the MgD2 phase. 相似文献
78.
Methods of bio-functionalize silicon nitride involve process steps to convert it into an oxynitride via plasma implantation
techniques. Such methods can potentially damage microstructures such as cantilevers. In this paper, we report successful bio-functionalization
of Hotwire CVD silicon nitride-based piezo-resistive cantilevers without any oxygen plasma treatment. Process to fabricate
such structures and to bio-functionalize them is discussed in detail. 相似文献
79.
Jelani Griffin Anant Kumar Singh Dulal Senapati Eumin Lee Kevin Gaylor Jeanette Jones‐Boone Paresh Chandra Ray 《Small (Weinheim an der Bergstrasse, Germany)》2009,5(7):839-845
The hepatitis C virus (HCV) is a single‐stranded (ss) RNA virus that is responsible for chronic liver diseases, such as cirrhosis, end‐stage liver disease, and hepatocellular carcinoma. Driven by the need to detect the presence of the HCV viral sequence, herein it is demonstrated for the first time that the nonlinear optical (NLO) properties of gold nanoparticles can be used for screening and quantifying HCV RNA without any modification, with excellent detection limit (80 pM ) and selectivity (single base‐pair mismatch). The hyper‐Rayleigh scattering (HRS) intensity increases 25 times when label‐free, 145‐mer, HCV ss‐RNA is hybridized with 400 pM target RNA. The mechanism of HRS intensity change is discussed with experimental evidence for a higher multipolar contribution to the NLO response of gold nanoparticles. 相似文献
80.
提出了将J2EE和CADRBA的集成应用于基于HDF4格式的遥感数据发布系统的思想,介绍了HDF4文件格式,阐述了该应用的必要性;分析了该模型的体系结构以及客户端、应用服务器端、CDRBA组件和数据库的设计过程;最后展望了该模型的应用前景。 相似文献